Various electronic components, such as printed circuits are mounted in enclosures which in turn are secured to rails of relay rack cabinets. Ideally, such enclosures should be easy to assemble with the electronic components therein and when necessary easy to disassemble. Conventionally, various types of fasteners, such as threaded fasteners are used to mount the top and bottom covers together. Once the enclosure is assembled it should also be easy to mount the enclosure in a reliable manner in the cabinet rack and similarly it should be easy to remove the enclosure. Such enclosure preferably should be shallow so that a large number of enclosures could be mounted in a single cabinet. Ideally such enclosures should also be inexpensive to make without detracting from their reliability.